From: Christoph Lameter <cl@linux.com>
To: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Mel Gorman <mgorman@suse.de>,
Andrew Morton <akpm@linux-foundation.org>,
Colin King <colin.king@canonical.com>,
Raghavendra D Prabhu <raghu.prabhu13@gmail.com>,
Jan Kara <jack@suse.cz>, Chris Mason <chris.mason@oracle.com>,
Pekka Enberg <penberg@kernel.org>, Rik van Riel <riel@redhat.com>,
Johannes Weiner <hannes@cmpxchg.org>,
linux-fsdevel <linux-fsdevel@vger.kernel.org>,
linux-mm <linux-mm@kvack.org>,
linux-kernel <linux-kernel@vger.kernel.org>,
linux-ext4 <linux-ext4@vger.kernel.org>
Subject: Re: [PATCH 3/3] mm: slub: Default slub_max_order to 0
Date: Thu, 12 May 2011 10:27:00 -0500 (CDT) [thread overview]
Message-ID: <alpine.DEB.2.00.1105121024350.26013@router.home> (raw)
In-Reply-To: <1305213359.2575.46.camel@mulgrave.site>
On Thu, 12 May 2011, James Bottomley wrote:
> > > */
> > > static int slub_min_order;
> > > -static int slub_max_order = PAGE_ALLOC_COSTLY_ORDER;
> > > +static int slub_max_order;
> >
> > If we really need to do this then do not push this down to zero please.
> > SLAB uses order 1 for the meax. Lets at least keep it theere.
>
> 1 is the current value. Reducing it to zero seems to fix the kswapd
> induced hangs. The problem does look to be some shrinker/allocator
> interference somewhere in vmscan.c, but the fact is that it's triggered
> by SLUB and not SLAB. I really think that what's happening is some type
> of feedback loops where one of the shrinkers is issuing a
> wakeup_kswapd() so kswapd never sleeps (and never relinquishes the CPU
> on non-preempt).
The current value is PAGE_ALLOC_COSTLY_ORDER which is 3.
> > We have been using SLUB for a long time. Why is this issue arising now?
> > Due to compaction etc making reclaim less efficient?
>
> This is the snark argument (I've said it thrice the bellman cried and
> what I tell you three times is true). The fact is that no enterprise
> distribution at all uses SLUB. It's only recently that the desktop
> distributions started to ... the bugs are showing up under FC15 beta,
> which is the first fedora distribution to enable it. I'd say we're only
> just beginning widespread SLUB testing.
Debian and Ubuntu have been using SLUB for a long time (and AFAICT from my
archives so has Fedora). I have been running those here for a couple of
years and the issues that I see here seem to be only with the most
recent kernels that now do compaction and other reclaim tricks.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2011-05-12 15:27 UTC|newest]
Thread overview: 77+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-11 15:29 [PATCH 0/3] Reduce impact to overall system of SLUB using high-order allocations Mel Gorman
2011-05-11 15:29 ` [PATCH 1/3] mm: slub: Do not wake kswapd for SLUBs speculative " Mel Gorman
2011-05-11 20:38 ` David Rientjes
2011-05-11 15:29 ` [PATCH 2/3] mm: slub: Do not take expensive steps " Mel Gorman
2011-05-11 20:38 ` David Rientjes
2011-05-11 21:10 ` Mel Gorman
2011-05-12 17:25 ` Andrea Arcangeli
2011-05-11 15:29 ` [PATCH 3/3] mm: slub: Default slub_max_order to 0 Mel Gorman
2011-05-11 20:38 ` David Rientjes
2011-05-11 20:53 ` James Bottomley
2011-05-11 21:09 ` Mel Gorman
2011-05-11 22:27 ` David Rientjes
2011-05-13 10:14 ` Mel Gorman
2011-05-12 17:36 ` Andrea Arcangeli
2011-05-16 21:03 ` David Rientjes
2011-05-17 9:48 ` Mel Gorman
2011-05-17 19:25 ` David Rientjes
2011-05-12 14:43 ` Christoph Lameter
2011-05-12 15:15 ` James Bottomley
2011-05-12 15:27 ` Christoph Lameter [this message]
2011-05-12 15:43 ` James Bottomley
2011-05-12 15:46 ` Dave Jones
2011-05-12 16:00 ` James Bottomley
2011-05-12 16:08 ` Dave Jones
2011-05-12 16:27 ` Christoph Lameter
2011-05-12 16:30 ` James Bottomley
2011-05-12 16:48 ` Christoph Lameter
2011-05-12 17:46 ` Andrea Arcangeli
2011-05-12 18:00 ` Christoph Lameter
2011-05-12 18:18 ` Andrea Arcangeli
2011-05-12 17:06 ` Pekka Enberg
2011-05-12 17:11 ` Pekka Enberg
2011-05-12 17:38 ` Christoph Lameter
2011-05-12 18:00 ` Andrea Arcangeli
2011-05-13 9:49 ` Mel Gorman
2011-05-15 16:39 ` Andrea Arcangeli
2011-05-16 8:42 ` Mel Gorman
2011-05-12 17:51 ` Andrea Arcangeli
2011-05-12 18:03 ` Christoph Lameter
2011-05-12 18:09 ` Andrea Arcangeli
2011-05-12 18:16 ` Christoph Lameter
2011-05-12 18:36 ` James Bottomley
2011-05-12 17:40 ` Andrea Arcangeli
2011-05-12 15:55 ` Pekka Enberg
2011-05-12 18:37 ` James Bottomley
2011-05-12 18:46 ` Christoph Lameter
2011-05-12 19:21 ` James Bottomley
2011-05-12 19:44 ` James Bottomley
2011-05-12 20:04 ` James Bottomley
2011-05-12 20:29 ` Johannes Weiner
2011-05-12 20:31 ` Johannes Weiner
2011-05-12 20:31 ` James Bottomley
2011-05-12 22:04 ` James Bottomley
2011-05-12 22:15 ` Johannes Weiner
2011-05-12 22:58 ` Minchan Kim
2011-05-13 5:39 ` Minchan Kim
2011-05-13 0:47 ` James Bottomley
2011-05-13 4:12 ` James Bottomley
2011-05-13 10:55 ` Mel Gorman
2011-05-13 14:16 ` James Bottomley
2011-05-13 10:30 ` Mel Gorman
2011-05-13 6:16 ` Pekka Enberg
2011-05-13 10:05 ` Mel Gorman
2011-05-12 16:01 ` Christoph Lameter
2011-05-12 16:10 ` Eric Dumazet
2011-05-12 17:37 ` Andrew Morton
2011-05-12 15:45 ` Dave Jones
2011-05-11 21:39 ` [PATCH 0/3] Reduce impact to overall system of SLUB using high-order allocations James Bottomley
2011-05-11 22:28 ` David Rientjes
2011-05-11 22:34 ` James Bottomley
2011-05-12 11:13 ` Pekka Enberg
2011-05-12 13:19 ` Mel Gorman
2011-05-12 14:04 ` James Bottomley
2011-05-12 15:53 ` James Bottomley
2011-05-13 11:25 ` Mel Gorman
2011-05-12 18:04 ` Andrea Arcangeli
2011-05-13 11:24 ` Mel Gorman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=alpine.DEB.2.00.1105121024350.26013@router.home \
--to=cl@linux.com \
--cc=James.Bottomley@HansenPartnership.com \
--cc=akpm@linux-foundation.org \
--cc=chris.mason@oracle.com \
--cc=colin.king@canonical.com \
--cc=hannes@cmpxchg.org \
--cc=jack@suse.cz \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@suse.de \
--cc=penberg@kernel.org \
--cc=raghu.prabhu13@gmail.com \
--cc=riel@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox